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Diffstat (limited to 'include/linux/dma-mapping.h')
-rw-r--r--include/linux/dma-mapping.h13
1 files changed, 10 insertions, 3 deletions
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index c7d9b1b14ce7..931b70986272 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -8,6 +8,12 @@
#include <linux/dma-direction.h>
#include <linux/scatterlist.h>
+/*
+ * A dma_addr_t can hold any valid DMA or bus address for the platform.
+ * It can be given to a device to use as a DMA source or target. A CPU cannot
+ * reference a dma_addr_t directly because there may be translation between
+ * its physical address space and the bus address space.
+ */
struct dma_map_ops {
void* (*alloc)(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp,
@@ -193,7 +199,7 @@ static inline int dma_get_cache_alignment(void)
#ifndef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
static inline int
-dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
+dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
dma_addr_t device_addr, size_t size, int flags)
{
return 0;
@@ -224,13 +230,14 @@ extern void *dmam_alloc_noncoherent(struct device *dev, size_t size,
extern void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_handle);
#ifdef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
-extern int dmam_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
+extern int dmam_declare_coherent_memory(struct device *dev,
+ phys_addr_t phys_addr,
dma_addr_t device_addr, size_t size,
int flags);
extern void dmam_release_declared_memory(struct device *dev);
#else /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
static inline int dmam_declare_coherent_memory(struct device *dev,
- dma_addr_t bus_addr, dma_addr_t device_addr,
+ phys_addr_t phys_addr, dma_addr_t device_addr,
size_t size, gfp_t gfp)
{
return 0;